Centrifugal governor for internal combustion engines



Feb. 23, 1937. N 2,071,641

' CENTRIFUGAL GOVERNOR'FOR INTERNAL COMBUSTION ENGINES I Filed July 17, 1934 FIGB A -3 INVENTOR GUSTAV LGNN A T I O RNEY Patented Feb. 23, 1937 UNITED STATES CENTRIFUGAL GOVERNOR FOR INTERNAL COMBUSTION ENGINES Gustav Lunn, Copenhagen, Denmark, assignor to Aktieselskabet Frichs, Aarhus, Denmark, a limited-liability company Application July 17, 1934, Serial No. 735,658 In Denmark August 3, 1933 1 Claim.

My invention relates to improvements in centrifugal governors for internal combustion engines having a large range of speed. In connection with this type of governors it has been proposed to let the governor adjust the timing of the fuel injection in accordance with the number of revolutions. The invention relates to a particularly simple device especially suited for this purpose.

The invention consists mainly in the feature, that the governor sleeve during its displacement besides its normal function, i. e. adjusting the amount of fuel injected at each working cycle also through suitable means of transmission creates a relative angular movement between the shaft of the fuel pump and the shaft from which the movement of said fuel pump shaft is derived, thus causing the desired alteration of the moment of the beginning of the fuel injection in relation to the dead points of the engine.

Further the invention consists in the feature, that the two shafts the relative angular position of which shall be adjustable, are arranged coaxial along with the governor sleeve, which then is made to act as a coupling capable of transmitting the rotation. Consequently the governor sleeve is connected with the two shafts in such a way that their relative angular position is altered, when the governor sleeve is displaced longitudinally.

The invention is further characterized by the feature that the governor sleeve and the shafts or parts in connection with these shafts are provided with sets of corresponding driving projections of which one set or both sets can be screwed or helical in such a manner that an axial displacement of the governor sleeve creates a relative angular movement between the two shafts. In this case further connecting and transmitting elements are superfluous and an extremely simple design is arrived at. The driving projections can consist of two sets of opposite arranged helical tongues and grooves, two sets of helical tongues and grooves arranged likewise but with different inclination or one set of helical and one set of axial tongues and grooves. It will be found advantageous, also on account of the reduced overall length of the device and simplifications in manufacture to arrange one set of the driving projections on the outside of the governor sleeve and the other set on the inside, and it has proved particularly advantageous to arrange the axial projections on the outside and the helical projections on the inside.

The invention is illustrated in the accompanying drawing, in which Figure 1 is a longitudinal section through a centrifugal governor, Fig. 2, a cross section through a governor, and Figs. 3 and 4, various details of same.

Similar numerals refer throughout the several views.

In Fig. 1 l is the fuel pump with shaft 2. On this a boss 3 is keyed, which is bored through and inside provided with flat axial surfaces 4 parallel to the pump shaft and engaging with corresponding flat surfaces 5 placed outside on the governor sleeve 6, which is bored through and on its inside is provided with helical projecting surfaces 1 engaging with corresponding projections 8 on the extended boss 9 of the toothed coupling ID. This coupling is engaging with a corresponding part (not shown) on the shaft, from which the rotary movement is derived and which in the following description is termed the driving shaft. In four-stroke-cycle engines the latter runs in synchronism with the cam shaft of the engine while in two-stroke-cycle engines it runs in synchronisrn with the crank shaft of the engine. The toothed coupling It runs in synohronism with the driving shaft. It should be noted that the extended boss 9 of the coupling H2 is carried and runs loose on an extension I i of the pump shaft 2.

Due to the driving surfaces and projections 4, 5 and l, 8 the governor sleeve 6 will act as a coupling forcing the boss 3 and consequently the pump shaft 2 to rotate with the same speed as the driving shaft and the coupling 65, and as one set of the driving surfaces l, 8 are of a helical form while the other set 4, 5 are axial, a longitudinal displacement of the governor sleeve will create relative angular movement between the pump shaft 2 and the driving shaft, hereby altering the moment of the beginning of the fuel injection in relation to the dead points of the engine.

I claim:

In combination, an internal combustion engine fuel pump having a driven shaft, a centrifugal governor support keyed thereon and having a tubular extension overlying the shaft end in concentric spaced relation, said extension being provided longitudinally with a pair of diametrically opposed slots, a rotary driving member having a sleeve freely rotatable on said shaft within said slotted extension, a collar axially slidable on said sleeve within said extension, drive lugs on said collar and engaged in the slots of said extension, centrifugal governor means on said support and in operative connection with said drive lugs whereby to move said collar axially as the governor operates, cooperative means on said sleeve and collar for rotating said collar and through it the governor support and driven shaft in synchronism with said driving member and sleeve, and said cooperative means effecting angular shifting between said driving member and the driven pump shaft as the collar is moved axially by operation of the governor.

to similar parts GUSTAV LUNN. 

